Hi,
this is a v3 patch set as a follow up of the thread about the errors reported by kselftest mixer-test. It changes HD-audio and vmaster control behavior to return -EINVAL for invalid input values.
There is a change in kselftest itself to skip the verification after write tests for volatile controls, too. It's for the channel map controls that can't hold the stable values.
v2->v3: * Replace with Mark's patch for kselftest * Apply the validation for user controls in put callback instead
v1->v2: * Skip only verification after write in kselftest * Add sanity check to HDMI chmap write, too
v2: https://lore.kernel.org/r/20240614153717.30143-1-tiwai@suse.de v1: https://lore.kernel.org/r/20240614124728.27901-1-tiwai@suse.de
Takashi
===
Mark Brown (1): kselftest/alsa: Fix validation of writes to volatile controls
Takashi Iwai (5): ALSA: vmaster: Return error for invalid input values ALSA: hda: Return -EINVAL for invalid volume/switch inputs ALSA: control: Apply sanity check of input values for user elements ALSA: chmap: Mark Channel Map controls as volatile ALSA: hda: Add input value sanity checks to HDMI channel map controls
sound/core/control.c | 6 ++- sound/core/pcm_lib.c | 1 + sound/core/vmaster.c | 8 ++++ sound/hda/hdmi_chmap.c | 18 +++++++++ sound/pci/hda/hda_codec.c | 23 +++++++++--- tools/testing/selftests/alsa/mixer-test.c | 45 +++++++++++++++-------- 6 files changed, 79 insertions(+), 22 deletions(-)
So far the vmaster code has been tolerant about the input values and accepts any values by correcting internally. But now our own selftest starts complaining about this behavior, so let's be picky and change the behavior to return -EINVAL for invalid input values instead.
Reported-by: Paul Menzel pmenzel@molgen.mpg.de Closes: https://lore.kernel.org/r/1d44be36-9bb9-4d82-8953-5ae2a4f09405@molgen.mpg.de Reviewed-by: Jaroslav Kysela perex@perex.cz Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/core/vmaster.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/sound/core/vmaster.c b/sound/core/vmaster.c index 04a57f7be6ea..c657659b236c 100644 --- a/sound/core/vmaster.c +++ b/sound/core/vmaster.c @@ -198,6 +198,12 @@ static int follower_put(struct snd_kcontrol *kcontrol, err = follower_init(follower); if (err < 0) return err; + for (ch = 0; ch < follower->info.count; ch++) { + if (ucontrol->value.integer.value[ch] < follower->info.min_val || + ucontrol->value.integer.value[ch] > follower->info.max_val) + return -EINVAL; + } + for (ch = 0; ch < follower->info.count; ch++) { if (follower->vals[ch] != ucontrol->value.integer.value[ch]) { changed = 1; @@ -365,6 +371,8 @@ static int master_put(struct snd_kcontrol *kcontrol, new_val = ucontrol->value.integer.value[0]; if (new_val == old_val) return 0; + if (new_val < master->info.min_val || new_val > master->info.max_val) + return -EINVAL;
err = sync_followers(master, old_val, new_val); if (err < 0)
So far the HD-audio driver has been tolerant about the input values and accepts any values by correcting the amp volume and switch values internally. But now our own selftest starts complaining about this behavior, so let's be picky and change the behavior to return -EINVAL for invalid input values instead.
Reported-by: Paul Menzel pmenzel@molgen.mpg.de Closes: https://lore.kernel.org/r/1d44be36-9bb9-4d82-8953-5ae2a4f09405@molgen.mpg.de Reviewed-by: Jaroslav Kysela perex@perex.cz Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/pci/hda/hda_codec.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-)
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c index 325e8f0b99a8..3dd1bda0c5c6 100644 --- a/sound/pci/hda/hda_codec.c +++ b/sound/pci/hda/hda_codec.c @@ -1496,7 +1496,7 @@ update_amp_value(struct hda_codec *codec, hda_nid_t nid, /* ofs = 0: raw max value */ maxval = get_amp_max_value(codec, nid, dir, 0); if (val > maxval) - val = maxval; + return -EINVAL; return snd_hda_codec_amp_update(codec, nid, ch, dir, idx, HDA_AMP_VOLMASK, val); } @@ -1547,13 +1547,21 @@ int snd_hda_mixer_amp_volume_put(struct snd_kcontrol *kcontrol, unsigned int ofs = get_amp_offset(kcontrol); long *valp = ucontrol->value.integer.value; int change = 0; + int err;
if (chs & 1) { - change = update_amp_value(codec, nid, 0, dir, idx, ofs, *valp); + err = update_amp_value(codec, nid, 0, dir, idx, ofs, *valp); + if (err < 0) + return err; + change |= err; valp++; } - if (chs & 2) - change |= update_amp_value(codec, nid, 1, dir, idx, ofs, *valp); + if (chs & 2) { + err = update_amp_value(codec, nid, 1, dir, idx, ofs, *valp); + if (err < 0) + return err; + change |= err; + } return change; } EXPORT_SYMBOL_GPL(snd_hda_mixer_amp_volume_put); @@ -2149,15 +2157,20 @@ int snd_hda_mixer_amp_switch_put(struct snd_kcontrol *kcontrol, int change = 0;
if (chs & 1) { + if (*valp < 0 || *valp > 1) + return -EINVAL; change = snd_hda_codec_amp_update(codec, nid, 0, dir, idx, HDA_AMP_MUTE, *valp ? 0 : HDA_AMP_MUTE); valp++; } - if (chs & 2) + if (chs & 2) { + if (*valp < 0 || *valp > 1) + return -EINVAL; change |= snd_hda_codec_amp_update(codec, nid, 1, dir, idx, HDA_AMP_MUTE, *valp ? 0 : HDA_AMP_MUTE); + } hda_call_check_power_status(codec, nid); return change; }
Although we have already a mechanism for sanity checks of input values for control writes, it's not applied unless the kconfig CONFIG_SND_CTL_INPUT_VALIDATION is set due to the performance reason. Nevertheless, it still makes sense to apply the same check for user elements despite of its cost, as that's the only way to filter out the invalid values; the user controls are handled solely in ALSA core code, and there is no corresponding driver, after all.
This patch adds the same input value validation for user control elements at its put callback. The kselftest will be happier with this change, as the incorrect values will be bailed out now with errors.
For other normal controls, the check is applied still only when CONFIG_SND_CTL_INPUT_VALIDATION is set.
Reported-by: Paul Menzel pmenzel@molgen.mpg.de Closes: https://lore.kernel.org/r/1d44be36-9bb9-4d82-8953-5ae2a4f09405@molgen.mpg.de Reviewed-by: Jaroslav Kysela perex@perex.cz Reviewed-by: Mark Brown broonie@kernel.org Reviewed-by: Takashi Sakamoto o-takashi@sakamocchi.jp Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/core/control.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/sound/core/control.c b/sound/core/control.c index fb0c60044f7b..1dd2337e2930 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -1480,12 +1480,16 @@ static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol, static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol) { - int change; + int err, change; struct user_element *ue = kcontrol->private_data; unsigned int size = ue->elem_data_size; char *dst = ue->elem_data + snd_ctl_get_ioff(kcontrol, &ucontrol->id) * size;
+ err = sanity_check_input_values(ue->card, ucontrol, &ue->info, false); + if (err < 0) + return err; + change = memcmp(&ucontrol->value, dst, size) != 0; if (change) memcpy(dst, &ucontrol->value, size);
From: Mark Brown broonie@kernel.org
When validating writes to controls we check that whatever value we wrote actually appears in the control. For volatile controls we cannot assume that this will be the case, the value may be changed at any time including between our write and read. Handle this by moving the check for volatile controls that we currently do for events to a separate block and just verifying that whatever value we read is valid for the control.
Signed-off-by: Mark Brown broonie@kernel.org Link: https://lore.kernel.org/r/20240614-alsa-selftest-volatile-v1-1-3874f02964b1@... Signed-off-by: Takashi Iwai tiwai@suse.de --- tools/testing/selftests/alsa/mixer-test.c | 45 +++++++++++++++-------- 1 file changed, 29 insertions(+), 16 deletions(-)
diff --git a/tools/testing/selftests/alsa/mixer-test.c b/tools/testing/selftests/alsa/mixer-test.c index 1c04e5f638a0..dd74f8cc7ece 100644 --- a/tools/testing/selftests/alsa/mixer-test.c +++ b/tools/testing/selftests/alsa/mixer-test.c @@ -625,6 +625,21 @@ static int write_and_verify(struct ctl_data *ctl, return err; }
+ /* + * We can't verify any specific value for volatile controls + * but we should still check that whatever we read is a valid + * vale for the control. + */ + if (snd_ctl_elem_info_is_volatile(ctl->info)) { + if (!ctl_value_valid(ctl, read_val)) { + ksft_print_msg("Volatile control %s has invalid value\n", + ctl->name); + return -EINVAL; + } + + return 0; + } + /* * Check for an event if the value changed, or confirm that * there was none if it didn't. We rely on the kernel @@ -632,22 +647,20 @@ static int write_and_verify(struct ctl_data *ctl, * write, this is currently true, should that ever change this * will most likely break and need updating. */ - if (!snd_ctl_elem_info_is_volatile(ctl->info)) { - err = wait_for_event(ctl, 0); - if (snd_ctl_elem_value_compare(initial_val, read_val)) { - if (err < 1) { - ksft_print_msg("No event generated for %s\n", - ctl->name); - show_values(ctl, initial_val, read_val); - ctl->event_missing++; - } - } else { - if (err != 0) { - ksft_print_msg("Spurious event generated for %s\n", - ctl->name); - show_values(ctl, initial_val, read_val); - ctl->event_spurious++; - } + err = wait_for_event(ctl, 0); + if (snd_ctl_elem_value_compare(initial_val, read_val)) { + if (err < 1) { + ksft_print_msg("No event generated for %s\n", + ctl->name); + show_values(ctl, initial_val, read_val); + ctl->event_missing++; + } + } else { + if (err != 0) { + ksft_print_msg("Spurious event generated for %s\n", + ctl->name); + show_values(ctl, initial_val, read_val); + ctl->event_spurious++; } }
The values returned from Playback Channel Map and Capture Channel Map controls may vary dynamically depending on the corresponding PCM stream. Mark those as volatile to indicate the values are unstable and not suitable for testing.
Note that we may change the driver to return -EINVAL, but this would bring other side effects, such as "alsactl restore" would start receiving unexpected errors. So we still keep returning 0 for those invalid inputs.
Reported-by: Paul Menzel pmenzel@molgen.mpg.de Closes: https://lore.kernel.org/r/1d44be36-9bb9-4d82-8953-5ae2a4f09405@molgen.mpg.de Reviewed-by: Jaroslav Kysela perex@perex.cz Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/core/pcm_lib.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 6f73b3c2c205..071c67cbc479 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -2556,6 +2556,7 @@ int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream, struct snd_kcontrol_new knew = { .iface = SNDRV_CTL_ELEM_IFACE_PCM, .access = SNDRV_CTL_ELEM_ACCESS_READ | + SNDRV_CTL_ELEM_ACCESS_VOLATILE | SNDRV_CTL_ELEM_ACCESS_TLV_READ | SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK, .info = pcm_chmap_ctl_info,
Add a simple sanity check to HD-audio HDMI Channel Map controls. Although the value might not be accepted for the actual connection, we can filter out some bogus values beforehand, and that should be enough for making kselftest happier.
Reviewed-by: Jaroslav Kysela perex@perex.cz Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/hda/hdmi_chmap.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+)
diff --git a/sound/hda/hdmi_chmap.c b/sound/hda/hdmi_chmap.c index 5d8e1d944b0a..7b276047f85a 100644 --- a/sound/hda/hdmi_chmap.c +++ b/sound/hda/hdmi_chmap.c @@ -753,6 +753,20 @@ static int hdmi_chmap_ctl_get(struct snd_kcontrol *kcontrol, return 0; }
+/* a simple sanity check for input values to chmap kcontrol */ +static int chmap_value_check(struct hdac_chmap *hchmap, + const struct snd_ctl_elem_value *ucontrol) +{ + int i; + + for (i = 0; i < hchmap->channels_max; i++) { + if (ucontrol->value.integer.value[i] < 0 || + ucontrol->value.integer.value[i] > SNDRV_CHMAP_LAST) + return -EINVAL; + } + return 0; +} + static int hdmi_chmap_ctl_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol) { @@ -764,6 +778,10 @@ static int hdmi_chmap_ctl_put(struct snd_kcontrol *kcontrol, unsigned char chmap[8], per_pin_chmap[8]; int i, err, ca, prepared = 0;
+ err = chmap_value_check(hchmap, ucontrol); + if (err < 0) + return err; + /* No monitor is connected in dyn_pcm_assign. * It's invalid to setup the chmap */
linux-kselftest-mirror@lists.linaro.org
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Takashi Iwai